Evaluation of Soybean Varieties and Advanced Lines Yield under Drought Stress Conditions using GGE Biplot Analysis

Evaluation of varieties and soybean lines under drought stress helps to breeders for detecting of stable and high-yielding genotypes. In this regard an experiment was conducted in randomized complete block design with three replications under normal and drought stress conditions across two locations (four environments). The results of combined analysis of grain yield/plant revealed effects of stress, location and genotype, interaction of stress × location, genotype × stress, genotype × location and genotype × stress × location were significant. In the present study was used GGE biplot method for assessment of 121 varieties and advanced lines of soybean across four environments. The results of biplot method showed that first and second components explained 66 and 22 percent (in total 88 percent) of total variation respectively. That is showing relatively good reliability in explanation of G variation. The results of graphical method showed Gonbad environments (normal and stress) and Rasht environments (normal and stress) were different each other in ranking and determine of adaption. In investigation of polygon biplot was observed in Rasht location under drought stress condition (RD), Gonbad location under normal condition (GN) and Gonbad location under drought condition (GD) genotypes 37 and 34 had the highest yield. In addition these three environments can be considered as one Mega-Environment. Several genotypes were located in sectors that no environments were placed. These genotypes had low yield in most environments. In stability ranking graph, genotypes 8, 9, 49, 63, 42, 86, 39 and 46 had moderate yield and high adaption and those had suitable combination of stability (adaptation) and yield.